Send Orders for Reprints to [email protected] Current Alzheimer Research, 2014, 11, 899-907
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Association of Smoking and Alcohol Drinking with Dementia Risk Among Elderly Men in China Shiming Zhou1, Rui Zhou2, Tingting Zhong1, Rui Li1, Jun Tan3 and Huadong Zhou1,* 1
Department of Neurology, Daping hospital, Third Military Medical University, Chongqing, China; 2Department of Orthopedics, the Orthopedic Surgery Center of Chinese PLA, Southwest Hospital, Third Military Medical University, Chongqing, China; 3Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Department of Psychiatry & Behavioral Neurosciences, Morsani College of Medicine; University of South Florida, Tampa, USA Abstract: Background: Previous studies relating smoking and alcohol drinking with the incidence of dementia have been inconsistent. Objectives: We assessed whether smoking and alcohol drinking was associated with the risk of dementia, including Alzheimer disease (AD) and vascular dementia (VaD) after seven years of follow-up. Design: We prospectively analysed the incidence of dementia from 2004 to 2011 among 2959 elderly men, according to their smoking and alcohol drinking status. Setting: six neighbourhoods from three districts mentioned in Chongqing city. Participants: A total of 3170 men were followed up annually for 7 years. Measurements: Cox proportional hazards models were established to evaluate the association between smoking, alcohol drinking and the risk of dementia. Results: The incidences of AD and VaD were higher respectively in current smoking than never smoking, daily drinking than never drinking over 7 years of follow-up (p 140/90 mmHg or being on antihypertensive treatment), diabetes mellitus (fasting blood glucose > 110 mg/dl or being on antidiabetic treatment), hypercholesterolemia (total cholesterol > 200 mg/dl). Measurements of blood pressure and electrocardiogram were performed on-site. In addition, fasting serum samples were collected at baseline and stored at -80°C for measurement of glucose, cholesterol and ApoE. Men with potential diseases that had not previously been diagnosed, were admitted to the Daping Hospital for further investigation and a diagnosis diseases state. The diagnosis of diseases, including ischemic heart diseases, stroke, hypertension, diabetes mellitus and hypercholesterolemia, were based on the International Classification of Diseases, 9th Revision (ICD-9). Smoking and Alcohol Drinking Tobacco smokers were classified as past smokers who had ceased smoking for at least 6 months, current smokers, or those who never smoked. Alcohol drinking status was classified as daily drinking, weekly drinking, monthly drinking, and occasional drinking. Non-smoking and drinking was neither smoking nor drinking, only smoking included past smoking and current smoking except drinking, only drinking included weekly drinking and monthly drinking except smoking. Co-smoking and drinking was defined as current smokers and daily drinking. In drinking men of our study, 86.3% men drank distilled spirit, 13.1% men drank beer, and only 0.6% men wine. In fact, 96.5% men drank distilled spirit and beer at the same time, so types of alcohol consumption were not analyzed in this study.
Zhou et al.
Diagnosis of Dementia The diagnosis of dementia was described in our previous studies [15]. In brief, diagnosis of dementia was based on criteria modified from the DSM-IV [16]. The subjects with dementia were further subjected to brain CT or MRI. Diagnosis of AD dementia was made according to the criteria of National Institute of Neurological and Communicative Diseases and Stroke/AD and Related Disorders Association [17]. Diagnosis of vascular dementia (VaD) was based on the criteria of the National Institute of Neurological Disorders and Stroke/Association Internationale pour la Recherche et l’Enseignement en Neurosciences (NINDS-AIREN) [18]. The differentiation of AD from VaD is based on the NINDSAIREN criteria and HIS (HIS4: AD, 4HIS7: mixed dementia (AD plus VaD), HIS 7: VaD [19]. The diagnosis of other dementias, including Parkinson's disease dementia, frontotemporal dementia, Lewy body dementia and Huntington’s disease, were based on the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) [16]. Follow-up A total of 3170 men were followed up annually for 7 years from July 2004 to June 2011. These men were interviewed by questionnaire and neuropsychological tests at the community medical centers or our staff went to their home to perform the interview when needed. Cognitive status was reassessed using the same neuropsychological tests as baseline screening. There was no difference in characteristics between dropped out and remained men in the study. Statistical Analysis Using univariate analyses, baseline variables between men with and without dementia were compared using the Pearson Chi square test, the Fisher exact test, the t test or the Mann-Whitney U test as deemed appropriate. We assessed the associations (hazard ratio) between smoking or drinking status and the risk of dementia development in the Cox proportional hazards models. The associations were firstly analyzed without adjustment for potential confounders. Then, the associations were further analyzed after adjustment for age BMI, education, ApoE and vascular risk factors. Finally, the statistical analyses were performed using SPSS 18.0 for Windows. RESULTS Baseline Characteristics in Men Who Did and Did not Develop Dementia In the seven years course of the study, 91 (2.9%) men died, 48 (1.5%) declined to further participate, and 72 (2.3%) moved away from the area, leaving 2959 men who completed the follow-up (Fig. 1). During follow-up, 357 cases of dementia were detected, of which 172 (48.2%) was AD, 156 (43.7%) were VaD and 29 (8.1%) were other dementias. For the men who completed the follow-up, the average age was 67.4±4.7 years. Compared with the men who did not develop dementia, those who did were significantly older, hypertension, diabetes mellitus, ischemic heart disease and stroke were more frequent in men with dementia, AD and VaD (p
899
Association of Smoking and Alcohol Drinking with Dementia Risk Among Elderly Men in China Shiming Zhou1, Rui Zhou2, Tingting Zhong1, Rui Li1, Jun Tan3 and Huadong Zhou1,* 1
Department of Neurology, Daping hospital, Third Military Medical University, Chongqing, China; 2Department of Orthopedics, the Orthopedic Surgery Center of Chinese PLA, Southwest Hospital, Third Military Medical University, Chongqing, China; 3Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Department of Psychiatry & Behavioral Neurosciences, Morsani College of Medicine; University of South Florida, Tampa, USA Abstract: Background: Previous studies relating smoking and alcohol drinking with the incidence of dementia have been inconsistent. Objectives: We assessed whether smoking and alcohol drinking was associated with the risk of dementia, including Alzheimer disease (AD) and vascular dementia (VaD) after seven years of follow-up. Design: We prospectively analysed the incidence of dementia from 2004 to 2011 among 2959 elderly men, according to their smoking and alcohol drinking status. Setting: six neighbourhoods from three districts mentioned in Chongqing city. Participants: A total of 3170 men were followed up annually for 7 years. Measurements: Cox proportional hazards models were established to evaluate the association between smoking, alcohol drinking and the risk of dementia. Results: The incidences of AD and VaD were higher respectively in current smoking than never smoking, daily drinking than never drinking over 7 years of follow-up (p 140/90 mmHg or being on antihypertensive treatment), diabetes mellitus (fasting blood glucose > 110 mg/dl or being on antidiabetic treatment), hypercholesterolemia (total cholesterol > 200 mg/dl). Measurements of blood pressure and electrocardiogram were performed on-site. In addition, fasting serum samples were collected at baseline and stored at -80°C for measurement of glucose, cholesterol and ApoE. Men with potential diseases that had not previously been diagnosed, were admitted to the Daping Hospital for further investigation and a diagnosis diseases state. The diagnosis of diseases, including ischemic heart diseases, stroke, hypertension, diabetes mellitus and hypercholesterolemia, were based on the International Classification of Diseases, 9th Revision (ICD-9). Smoking and Alcohol Drinking Tobacco smokers were classified as past smokers who had ceased smoking for at least 6 months, current smokers, or those who never smoked. Alcohol drinking status was classified as daily drinking, weekly drinking, monthly drinking, and occasional drinking. Non-smoking and drinking was neither smoking nor drinking, only smoking included past smoking and current smoking except drinking, only drinking included weekly drinking and monthly drinking except smoking. Co-smoking and drinking was defined as current smokers and daily drinking. In drinking men of our study, 86.3% men drank distilled spirit, 13.1% men drank beer, and only 0.6% men wine. In fact, 96.5% men drank distilled spirit and beer at the same time, so types of alcohol consumption were not analyzed in this study.
Zhou et al.
Diagnosis of Dementia The diagnosis of dementia was described in our previous studies [15]. In brief, diagnosis of dementia was based on criteria modified from the DSM-IV [16]. The subjects with dementia were further subjected to brain CT or MRI. Diagnosis of AD dementia was made according to the criteria of National Institute of Neurological and Communicative Diseases and Stroke/AD and Related Disorders Association [17]. Diagnosis of vascular dementia (VaD) was based on the criteria of the National Institute of Neurological Disorders and Stroke/Association Internationale pour la Recherche et l’Enseignement en Neurosciences (NINDS-AIREN) [18]. The differentiation of AD from VaD is based on the NINDSAIREN criteria and HIS (HIS4: AD, 4HIS7: mixed dementia (AD plus VaD), HIS 7: VaD [19]. The diagnosis of other dementias, including Parkinson's disease dementia, frontotemporal dementia, Lewy body dementia and Huntington’s disease, were based on the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) [16]. Follow-up A total of 3170 men were followed up annually for 7 years from July 2004 to June 2011. These men were interviewed by questionnaire and neuropsychological tests at the community medical centers or our staff went to their home to perform the interview when needed. Cognitive status was reassessed using the same neuropsychological tests as baseline screening. There was no difference in characteristics between dropped out and remained men in the study. Statistical Analysis Using univariate analyses, baseline variables between men with and without dementia were compared using the Pearson Chi square test, the Fisher exact test, the t test or the Mann-Whitney U test as deemed appropriate. We assessed the associations (hazard ratio) between smoking or drinking status and the risk of dementia development in the Cox proportional hazards models. The associations were firstly analyzed without adjustment for potential confounders. Then, the associations were further analyzed after adjustment for age BMI, education, ApoE and vascular risk factors. Finally, the statistical analyses were performed using SPSS 18.0 for Windows. RESULTS Baseline Characteristics in Men Who Did and Did not Develop Dementia In the seven years course of the study, 91 (2.9%) men died, 48 (1.5%) declined to further participate, and 72 (2.3%) moved away from the area, leaving 2959 men who completed the follow-up (Fig. 1). During follow-up, 357 cases of dementia were detected, of which 172 (48.2%) was AD, 156 (43.7%) were VaD and 29 (8.1%) were other dementias. For the men who completed the follow-up, the average age was 67.4±4.7 years. Compared with the men who did not develop dementia, those who did were significantly older, hypertension, diabetes mellitus, ischemic heart disease and stroke were more frequent in men with dementia, AD and VaD (p
